"Not a single state or territory treasurer has been asking for this tax to be reduced or removed from sanitary products," Senator Stoker said.

Some Liberal MPs have sought to lobby Treasurer Scott Morrison to remove the tax but he argues it would need the support of all states and territories to approve any changes to the GST.

Labor deputy leader Tanya Plibersek told AAP it was fair tax reform.

"It's time this arrogant and out-of-touch prime minister gave women a tax cut, instead of his mates at the big banks," Ms Plibersek said.

Labor announced in April that if elected to government, the tax would be removed.

Australian women spend around $300 million on sanitary products - tampons and pads - each year.

The tax component is about $30 million a year.

Under Labor's proposal, the loss of revenue to the states from GST on sanitary items would be offset by applying the GST consistently to 12 natural therapies that are sometimes GST free, such as herbalism and naturopathy.